This review summarizes the energy recommendation adopted in the Dietary Reference Intakes for Japanese 2020 (DRIs 2020). DRIs 2020 is designed to prevent the progression of frailty and malnutrition among older individuals as well as the onset and progression of chronic diseases such as hypertension, dyslipidemia, diabetes, and chronic kidney disease. In DRIs 2020, BMI (target BMI range) was adopted as the reference for maintaining an equilibrium between appropriate energy intake and expenditure. The target BMI range was defined for four adult age categories. Basically, the ranges were determined based on BMI values with the lowest all-cause mortality reported in observational epidemiological studies. However, for individuals aged 65 years and over, a tentative BMI range was determined by considering the actual BMI distribution for this age population and the obesity-related increased risk of disability.

This study aimed to clarify the association between a Japanese well-balanced diet and eating behavior in young adults. The subjects were respondents involved in the 2016 Hyogo Diet Survey. Among them, data for 343 male and female respondents aged 20‐39 years without any missing items were used for analysis. The subjects were divided into two groups based on their weekly consumption of a Japanese well-balanced diet (i.e., staple food, main, and side dishes) at least twice a day and their eating behaviors were compared using the chi-squared test. Using each eating behavior as an independent variable and the Japanese well-balanced diet as the dependent variable, logistic regression analyses were then conducted after adjusting for sex, age, residence status, employment status, and BMI. As a result, 227 (66.2％) and 116 (33.8％) respondents were classified into groups showing a high and low frequency of consumption of a Japanese well-balanced diet (HFJWBD: ≥4 times per week, LFJWBD: ≤3 times per week), respectively. The logistic regression analysis demonstrated a significantly higher odds ratio for HFJWBD among respondents who ate breakfast frequently (≥4 times per week), ate out less (≤3 times per week), and ate rice frequently (≥5 times per week). In conclusion, eating breakfast frequently, eating out less, and eating rice frequently were associated with a high frequency of consuming a Japanese well-balanced diet.